Sweeping devices of the kind mentioned above are known in a number of designs. Reference is made to the following patent disclosures: U.S. Pat. Nos. 2,834,034, 2,933,748, 3,087,180, and 3,354,489. Prior art also includes, see for example U.S. Pat. No. 2,933,748, the possibility of moving the brush cylinder between an upper disengaged position and a lower working position. The known devices, however, do not allow the operator to adjust without difficulty the pressure of the brush against the surface to be swept or to make the brush follow an uneven surface. The known devices fail, for example, to provide for the possibility of sweeping a depression in the surface between the front and rear wheels of the sweeping apparatus.
There have been presented sweepers, the rotatable brush of which can be made to pivot about a vertical axis, thereby allowing for so called diagonal sweeping, changing the angle between the brush axis and the carriage is a complicated procedure, however, and the devices intended for diagonal sweeping have a complex construction.
In order to compensate to some degree for the fact that the brush cannot follow the swept surface if the surface is uneven, some known devices increase the pressure of the brush against the surface. As a consequence, however, the sweeping resistance increases correspondingly. If said resistance is also increased by the weight and/or the resistance of the sweepings, the result of the sweeping often becomes unsatisfactory. This is true for example when the surface to be swept is wet, or when wet snow or leaves or the like is to be removed.